Internal combustion engine



March 21, 1933. H. o, EW|NG INTERNAL coMBUsTIoN ENGINE Filed July 25. 1927 3 Sheets-3h66?. l

H. O. EWING INTERNAL GoMBUsTIoN ENGINE March 21, 1933.

Filed July 23, 1927 5 Sheets-Sheet 2 March 21, 1933. l||. o. EwlNG 1302,02()

INTERNAL coMBUsTIoN ENGINE Filed `my 23, 1927 5 sheets-sheet @Hoz/nav,

Patented Mar. 21, 1933 ik UNITED STATES HERBERT o. nwING, or MnmnEPORT,v omo INTERNAL ooitnsusfliroix]` Interner.y n

Application mea July 23,

This invention relatesto an internal combustion engine ofthe two cycle typeone of the objects beingto provide an engineof increased power and -eiciency utilizing a vacuum Cylinder which, by reason of the construction and operation of the engine, can be made much smaller ,thanhas heretofore been possible where vacuum has been utilized as a means for exhausting burned gases from the combustion chamber. y

Another object is to provide'an engine of Vthe class described the cylinders and pistons of which can be lubricated in the'usual way, that is to'say, either by the splash or `pump systems.

Another object is to utilize a vacuum cylinder and piston so assembled and'operating that the piston can start with av practically zero clearance and will operate to expel all cylinder being so arranged that it will not be heated by the gases in the combustion chamber and can, therefore, be kept cool Vmore readily than heretofore. s i

With the foregoing andA other objectsin view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the Vscope of what is claimed, without departing from the spirit of the invention.

In the accompanying drawings, the preferred form of the invention has been shown.

In said drawings, Y' Figure lisa section through the engine showing the relative positions of the parts at 40 the beginning of the explosion stroke.

Figure 2 is a similar view showing the relative positions oi the parts ljust prior to the completion of the explosion stroke. 1 .c

Figure 3 is a similar view showing the relative positions of the parts at the beginning Vot' the compression stroke.

Figure 4l shows the engine with the parts positioned during the first part of their move- 1 Vment from the positions shown in Figure 3.

Figure 5 is a'section showing the positions or practically all burned gases, the vacuumv 1927. serial No. 207,915. 1

assumed by the pistons immediately 'following the positions illustrated in Figure 4. V- .Figure 6 -is asection through they engine showing the` parts. positioned at theiend of the compressionv stroke, the zero clearance in 455 the vaouumfcylinder being indicated.

Referringto thefigures by characters of Y l reference 1 and 2 designate thetwo cylinf ders of the engine communicating at one end with the crankcase and having their outer Q0 portions Awater.` cooled asv indicated at 4. These cylinderscan'be castl inone block with Y their heads and 6 removably mountedto give convenient access to the interiors of the cylinders. The cylinders are disposed at acute angles to each other so that the wall of the cylinder 2 willv not be heated by the gases within the cylinder 1. f Consequently thecylkinder 2 can -be maintained at a comparatively low temperature. Cylinder 1, which `con- 70 tains the combustion vchamber 7, is provided with the usual Vspark plug 8 in the head1 5 thereof while the head 6of `cylinder 2 has-an `outletportion) communicating'with an eX- haust Ypassage-10,- the saidport beinglnor# .'ma-lly closed yby, a valve 11'Y adapted. to lbe n lifted Vbygpre'ssure fro-m-within'the cylinder 2;y This valve is normally held to its seat by` a spring 12, in the structure illustrated but itis to be'understood thatV other types vof 30 valves maybe used if desired;` 'i f Y '1 At agpoint between its ends thevcylinder- 1 is provided with an intake 'port 13 and opening into the same cylinder at a point opposite the'port 13, is a transfer passage 14185 one end of which opens into the cylinder .2 as shown at-15 while theotherend opens into the combustion chamber 7 as shown at 16. This end 16constitutestheinlet to the .port 14 and is'enlarged in the direction of the head :.90V

5 as shown at 17. A p'owerpiston` 18" is l mounted for reciprocation within the cylinder 1 and isconnected by a pitman 19 to the Y crank 20 in the case `3. l Another piston 21 is mounted to reciprocate within the cylinderA 2 and is connected by a pitman 22 to the pite man 19 asshown at 23. The ports 13 and 16 are so positioned Yrelative toeach other.` 'and to the head of the piston that, during a short interval while theengine in operation the operation of the engine, the piston 21 willA cl-ose communication between the port 14 and the vacuum chamber 24 while at the Asame time the combustion chamberv 7 is in communication with passage -14 and either in or out of communication with the lportA 13 as shown in Figures 4 and 5 respectively. The proper lead of the piston in the vacuum cylinder 2 in its movement relative to the piston 18 in the combustion cylinder is insured because of the particular acute angle at which the two cylinders are arranged. The relative positions of the parts at different stages during the operation of the Yengine are of importance as will be apparent in the following descriptionof the operati-on:

Assuming that'the pistons 18 and 21 are .inthe positions shown in FigureV 1, the piston 21 having moved downwardly .from a zero clearance Vagainst the head 6 and' an explosion havin()r just occurred in the chamber 7', the two pistons will move downwardly under the power exerted by the expanded eX- ploded gases in chamber 7. VThe particular 'pitman connection provided for the piston 21 willcause it to move downwardly past the p0rt'15 so as to uncover it before the ports 13 and 16 have been uncovered. Consequently a vacuum willbe produced within the chamber 24, the outside pressure serving to hold Vthe valve 11 tightly upon its seat. These positions of the parts have been illustrated in Figure 2. VImmediately following this'action the descending piston 18 `uncovers first the port 16 .and'then the port 13. y As aresultthe burned gases will rush into thepassage 14 and thenceto the vacuum chamber 24. This action, as welll as the cooling and shrink- Yage of the burned gases following the explosion will cause the. pressure within the vacuum chamber as well as in the. combustion chamber to be brought to several pounds below atmospheric pressure. During continued ,downwardly movement of thepiston 18 following the. partial uncovering of the port 16 and the escape of burned gases to the vacuum chamber, the intake porti 13 is opened as Yshown in Figure 3. This will result in the admission of the explosive mixture and as atmospheric'press'ure is greater than the pressure within the cylinders the fresh supply of gas will flow automatically into the combustion chamber 7 where it will strike the deflector 25k on the piston 17 which deflector is located close to thefport 13. .Consequently the l imushing fuel, being subjected to very little tion of its exhaust stroke has resistance from the gaseous contents of the engine, will flow easily toward the head 5 where it will be turned back and practically all of the remaining burned gases within the combustion chamber will flow into the port ""3 16 and passage 14, leaving the combustion chamber almost entirely free of burned gases. As the new charge of cold gas enters the combustion chamber 7 it operates to further chill thecylinder 1. i 75 Immediately following the admission of the chargev of mixture to the combustion chamber, with the parts positioned as in Figure 3, the piston 21 moves upwardly slightly Y in advance of the piston 18 and'closes the port 80 15 so that the unburned mixture Anow flowing y into'the combustion chamber vand the port 13 cannot enter the vacuum cylinder.

As the gas within the chamber 7 was Well below atmospheric pressure at the time the .85 portl=5 was closedby the piston 21, further gas can enter the combustion chamber 7 before the piston-18 fully closes the port 13.

The amount vof gas thus admitted will be sufficient to raise the pressure in the combustion i chamber' 7 to atmospheric pressure without resulting in anyl loss of gas through the port 16 and passage 14. rlhe relative positions of the partsat this-time have been illustrated, in Figure 4. It might be stated that as the vacuum chamber was not restored to full latmopheric pressure during the foregoing operation, the resistance to the upward stroke `of the piston 21 will be reduced and compres sion of the charge in the explosion chamber 'i190 7Vwill be facilitated; As thev crank shaft moves from the position shown in Figure 4 both pistons will be moved towardv the respective cylinder heads, thereby lcompletely closing first the port '13 and then the port 16 1&05 as will be obvious by referring to Figure 5. Further movement will bring the piston 21 flat against the head 6 so as to produce zero clearance. lThe vacuum'chamb'er is several pounds below atmosphericpres'sure until the C310 piston has traveled far enough to overcome this subfatmospheric pressure after which it creates a pressure great enough to open the spring pressed valve 11. It is on this stroke and due to thiscondition that a partvof the energy required to produce the vacuum is restored to the crankshaft. Meanwhile the charge in the combustion chamber 7 is being compressed and at the end ofthe compression 120 stroke this charge will be ignited so that the operation will be repeated asbeforedescribed. The position of the piston 21 at the complebeen illustrated in Figure 6.

'-125 Importance is attached to the fact that, as

'the ort'15 closes before the frases in the Compression stroke.

required to actuate the engine during the In the present engine cooling occurs inthe combustion chamber much the same as VV1n other engines, except that it takes place much faster than in other engines because of the fact that the pressure drop is so much faster due tothe sub-atmospheric pressure within the vacuum chamber to which the gas is so rapidly being transferred. A Then too as this operation is progressing the pressure within the combustion chamber also goes from six to ten pounds below atmospheric. 'This has been disclosed by actual tests. This also keeps down temperature.

Many inventors have had in mind various means of handling this proposition all of y which have differed from the'present invention in that they provide means to use an auxengine, communication is cut off from the combustion chamber earlier than heretofore which permits the burned gases to cool better and drop farther below atmospheric pressure and so give back to the crank shaft more of the energy required to produce the vacuum, thus adding to the power output of the en- It is to be understood of course that the term vacuum used in the foregoing speciication and in the appended claim is not intended to mean an absolute vacuum.

What is claimed is:

In a two-cycle internal combustion engine the combination with a power cylinderand a vacuum cylinder disposed at a relatively Y small angle to each other, of an intake port BLS opening into the power cylinder, a valved exhaust port in the head of the vacuum cylinder, a relatively short passage connecting the cylinders at a point between their lower ends, a piston in the power. cylinder for successively opening thecylinder to the passage and to the intake port during the explosion stroke and successively closing the intake port and the passage during the compression stroke, a piston in the vacuum cylinder, a crank shaft, a pitman connection between the crank shaft and the piston in the power cylinder, and a shorter pitman connection between the pitman of the power piston'and the piston in the vacuum cylinder,said pitmansand crank shaft cooperating to a'ctuate the vacuum piston to move from a Zero clearance and create a vacuum during the explosion stroke of the power piston andthereafter to open and close the cylinder to the passage, said passage being adapted to be closed by the vacuum piston prior to the compression of gases in the vacuum cylinder and v,before the closing of the intake port by the piston in the power cylinder. e Y

In testimony that I claim the'foregoing as my own, I have hereto aiixed my signature.

HERBERT O. EWING. 

